> In the new-drivers document, under the heading "Write the new driver", > it says: > > "Remember that you want to output the direct measurements done by > the chip. If these sensor values need scaling, this should be done > through the configuration file." > > However, many of the existing drivers don't do this. For example, > lm85.c has this macro: > > #define FAN_FROM_REG(val) ((val)==0?-1:(val)==0xffff?0:5400000/(val)) > > which the driver uses to convert from register values to rps. There > are lots of similar constructs in other drivers. > > Which is the right way for new drivers - the code or the > documentation? The documentation sure would need some clarifications. Yes, most drivers convert values to output useful information. Chips behave too differently and it would be a complete mess if we were really outputing raw values (what would the drivers be worth to then?). I think that what the documentation tries to prevent there is hardcoding resistor values for +5V, +12V, -12V and -5V. These values are likely to change from motherboard to motherboard, and that's why they are set in /etc/sensors.conf. For the rest, drivers tend to convert from registers to "real" values (that is, values that make direct sense for a human being). Most of the time you will want to believe the driver code :) However, the best thing to do would be to fix the documentation to match what we actually do. I have made some modifications to the documentation at the time I wrote a chip driver myself, feel free to do the same. And don't hesitate to ask other questions that may come to your mind :) -- Jean Delvare http://www.ensicaen.ismra.fr/~delvare/
